The Doomsday Clock, a metaphoric measure of the threat posed by nuclear weapons, biotechnology, and climate change, has been moved back one minute, to six minutes before midnight, signaling a more "hopeful state of world affairs."

The Bulletin of Atomic Sciences cited the increased discourse on climate change and further developments towards a nuclear weapons-free future as the cause for dialing back the clock.

It is 6 minutes to midnight. We are poised to bend the arc of history toward a world free of nuclear weapons. For the first time since atomic bombs were dropped in 1945, leaders of nuclear weapons states are cooperating to vastly reduce their arsenals and secure all nuclear bomb-making material. And for the first time ever, industrialized and developing countries alike are pledging to limit climate-changing gas emissions that could render our planet nearly uninhabitable. These unprecedented steps are signs of a growing political will to tackle the two gravest threats to civilization — the terror of nuclear weapons and runaway climate change.

This is the nineteenth time the clock has been changed since it was originally set at seven minutes to midnight in 1947. It has been as close to two minutes to midnight—in 1953, at the height of the Cold War—and as far away as 17 minutes to midnight, in 1991. [TurnBackTheClock.org]